NXP800 for the Treatment of Patients With Advanced or Metastatic Cholangiocarcinoma

Inclusion Criteria: * Age ≥ 18 years * Histologically/cytologically confirmed biliary tract cancer * Advanced or metastatic disease that is refractory to gemcitabine or fluoropyrimidine based therapy, or if there is intolerance to these regimens * Measurable disease by RECIST 1.1 * Eastern Cooperative Oncology Group (ECOG) performance status (PS) 0 or 1 * Anticipated life expectancy of \> 12 weeks * Hemoglobin ≥ 9.0 g/dL (obtained ≤ 14 days prior to registration) * Absolute neutrophil count (ANC) ≥ 1500/mm\^3 (obtained ≤ 14 days prior to registration) * Platelet count ≥ 100,000/mm\^3 (obtained ≤ 14 days prior to registration) * Aspartate aminotransferase (AST) ≤ 5 x upper limit of normal (ULN) (obtained ≤ 14 days prior to registration) * Alanine aminotransferase (ALT) ≤ 5 x ULN (obtained ≤ 14 days prior to registration) * Total bilirubin ≤ 1.5 x ULN (obtained ≤ 14 days prior to registration) * Serum creatinine ≤ 1.5 x ULN (obtained ≤ 14 days prior to registration) * Provide written informed consent * Negative pregnancy test done ≤ 7 days prior to registration, for persons of childbearing potential only * NOTE: If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required * Willing to use a highly effective method of contraception from the first dose of study medication through 180 days after the last dose of study medication, for persons of childbearing potential or persons able to father a child only * Willing to return to enrolling institution for follow-up (during the active monitoring phase of the study) Exclusion Criteria: * Any of the following because this study involves an investigational agent whose genotoxic, mutagenic, and teratogenic effects on the developing fetus and newborn are unknown: * Pregnant persons. * Nursing persons. * Persons of childbearing potential who are unwilling to employ adequate contraception * Systemic anti-neoplastic therapy or radiation therapy ≤ 14 days prior to registration * Major surgical procedure ≤ 28 days prior to registration * Ongoing therapy related events \> grade 2 * Presence of another primary malignancy not in remission * New York Heart Classification 3 or greater heart failure * QT/corrected QT (QTc) interval \> 470 ms using Fredericia's QT correction formula * Uncontrolled brain metastatic disease * Uncontrolled infection * Any other comorbidities within the opinion of the investigator interfere with the investigation of the protocol * Usage of drugs that strongly inhibit or induce CYP3A4 ≤ 7 days prior to registration and for the duration of NXP800 dosing. Drugs that are low, medium, or other inhibitors of CYP3A4 are not prohibited and should be used with caution. Drugs that inhibit BCRP are not prohibited but should be used with caution, since NXP800 was found to be a BCRP substrate * Usage of seville oranges, grapefruit or grapefruit juice or products ≤ 7 days prior to registration and for the duration of NXP800 dosing * Unwillingness to follow study related procedures * Inability to provide informed consent